The present invention relates to inhibited 1,1,1-trichloroethane compositions.
The use of 1,1,1-trichloroethane as a solvent with applications in dry cleaning, industrial cleaning and degreasing operations is well-known. It is also known to use 1,1,1-trichloroethane as a solvent in adhesive, coating and ink formulations. The tendency of 1,1,1-trichloroethane to degrade in the presence of metals, particularly aluminum, and moisture is also recognized. Thus, it has long been customary to add stabilizing amounts of inhibitors to 1,1,1-trichloroethane to stabilize it against metal-induced decomposition and to prevent corrosive attack upon the metal surfaces in contact with it.
Numerous examples exist of inhibitor compositions which have been taught to be useful in the inhibition of 1,1,1-trichloroethane. U.S. Pat. No. 3,113,154 teaches that 1,1,1-trichloroethane is stabilized by a mixture of dioxolane, an amine and a mono-olefin. U.S. Pat. No. 3,397,148 teaches that 1,1,1-trichloroethane is stabilized against metal corrosion with dioxolane and an epoxide. U.S. Pat. No. 4,018,837 teaches that a mixture of (1) a monoepoxide, a monochloroepoxide or mixture thereof and (2) a three-component mixture selected from dioxane, dioxolane, trioxane, tertiary butyl alcohol and a nitroalkane is useful to stabilize 1,1,1-trichloroethane. U.S. Pat. No. 4,115,461 teaches generally that 1,1,1-trichloroethane may be stabilized using a mixture comprising an epoxide, dioxolane, a nitroalkane and an alcohol. U.S. Pat. No. 4,189,397 teaches that 1,1,1-trichloroethane is stabilized with a low molecular weight polyalkylene glycol monoalkyl ether. U.S. Pat. No. 3,074,890 teaches that diethylene glycol dimethyl ether stabilizes 1,1,1-trichloroethane against decomposition when in contact with aluminum. U.S. Pat. No. 2,371,645 teaches that certain ethers inhibit the corrosion of chlorinated solvents used in various degreasing processes.
The known inhibited 1,1,1,-trichloroethane formulations are not without problems. Generally, these formulations have been developed for use in vapor degreasing and cold metal cleaning operations. Thus, the formulations known may not be well adapted for use in coating and ink applications. Further, many of the accepted inhibitors have become unacceptable from an environmental and/or toxicological perspective. Thus, what is lacking and what is needed is an inhibited 1,1,1-trichloroethane composition well adapted for use in coatings and inks which is environmentally acceptable.